Modding some extra boost for a bus

How to learn modding in OMSI? I need to increase the volume of acceleration of MAN SD202 D92 by 1.5x (50% more acceleration). I found engine_constfile_D92 but I can't succesfully continue. I haven't modified any vehicles in any games before. I'm making an 100% electic MAN SD202 D92 bus and I have the engine etc sounds modified now but now I need to increase the acceleration to imitate the boost of an electric motor. Thanks already!